I'll post this explanation and then go back to mostly ignoring the situation. It deals with "extreme" trolling, but seems to apply to some degree here as well.

"It just makes me happy when I can make someone angry. It sounds weird but I kind of feed off their anger. The angrier I can get them, the better I feel," he told news.com.au....He said a sense of power was important to how people behaved online. "You're far more likely to be a troll if you’re a relative weakling elsewhere," he said.